This paper treats the problem of the penetration of a cylindrical leg of a fixed offshore structure into the sea. The problem is taken as a classic contact problem where the seabed is flat and two cases of structure geometry are considered. Comparisons of the flat and hemispherical bottom geometries indicate that the hemispherical geometry requires 2/3 the load of the flat bottom. This results leads to a preliminary conclusion that a hemispherical geometry is more efficient for initial penetration. © 1985.